- FreeList: enforce min 16B alignment, use GCHandle for SharedState lifetime, switch to AllocZeroed, and use MemoryUtility for oversized allocs
- Add FreeList.CollectLocal() to flush thread-local caches
- TLSF: add decommitted flag, support front splitting for alignment, add Collect() to decommit large free blocks, use Munmap for cleanup
- Add VirtualMemoryBlock for virtual memory management
- Add tests for CollectLocal (FreeList) and Collect (TLSF)
- Update default allocator config and minor .csproj cleanup
